如何在自定義navigationController代碼中定位特定的viewController？

Question

我有這樣的習俗navigationController動畫我想要實現，但我想要的代碼被執行，只有當一個特定的viewController是在棧上。這裏是代碼：

class ARNImageTransitionNavigationController: UINavigationController, UINavigationControllerDelegate { 

    weak var interactiveAnimator : ARNTransitionAnimator? 
    var currentOperation : UINavigationControllerOperation = .None 

    override func viewDidLoad() { 
     super.viewDidLoad() 

     self.interactivePopGestureRecognizer?.enabled = false 
     self.delegate = self 
    } 

    func navigationController(navigationController: UINavigationController, 
     animationControllerForOperation operation: UINavigationControllerOperation, 
     fromViewController fromVC: UIViewController, 
     toViewController toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? 
    { 
     self.currentOperation = operation 

     if let _interactiveAnimator = self.interactiveAnimator { 
      return _interactiveAnimator 
     } 

     if operation == .Push { 
      return ARNImageZoomTransition.createAnimator(.Push, fromVC: fromVC, toVC: toVC) 
     } else if operation == .Pop { 
      return ARNImageZoomTransition.createAnimator(.Pop, fromVC: fromVC, toVC: toVC) 
     } 

     return nil 
    } 

    func navigationController(navigationController: UINavigationController, interactionControllerForAnimationController animationController: UIViewControllerAnimatedTransitioning) -> UIViewControllerInteractiveTransitioning? { 
     if let _interactiveAnimator = self.interactiveAnimator { 
      if self.currentOperation == .Pop { 
       return _interactiveAnimator 
      } 
     } 
     return nil 
    } 
} 

現在我該怎麼添加這段代碼確保它實現了它的所有方法，但只有當特定的viewController在堆棧上時纔會執行它。

Answer 1

如果你已經給有問題的視圖控制器提供了單獨的swift類，那麼你可以檢查他們的文件類名。假設您在推動時需要此動畫，例如導航堆棧的ProfilePageViewController，然後使用if operation == .Push && toVC.isKindOfClass(ProfilePageViewController)。我在您提供的代碼示例中添加了其餘代碼。

func navigationController(navigationController: UINavigationController, 
    animationControllerForOperation operation: UINavigationControllerOperation, 
    fromViewController fromVC: UIViewController, 
    toViewController toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? 
{ 
    self.currentOperation = operation 

    if let _interactiveAnimator = self.interactiveAnimator { 
     return _interactiveAnimator 
    } 

    if operation == .Push && toVC.isKindOfClass(swiftNameofVCClassFile) { 
     return ARNImageZoomTransition.createAnimator(.Push, fromVC: fromVC, toVC: toVC) 
    } else if operation == .Pop && fromVC.isKindOfClass(swiftNameofVCClassFile) { 
     return ARNImageZoomTransition.createAnimator(.Pop, fromVC: fromVC, toVC: toVC) 
    } 

    return nil 
} 

Answer 2

此，我們用它來獲得從NavigationController特定視圖控制器代碼堆棧：

if let viewController: MyViewController = HGViewStask.findControllerForType() { 
    // Your code 
} 

不幸的是，這些功能：

class HGViewStack{ 
    static func findControllerForType<T>() -> T? { 
     let navController: UINavigationController = HGApp.sharedApplication().keyWindow?.rootViewController as! UINavigationController 
     let controller: [T] = navController.viewControllers.filter({ $0 is T }).map({$0 as! T}) 
     return controller.first 
    } 
} 

您可以在這裏定義一樣，您的所有功能，使用它會影響你所有的控制器，他們只是沒有效果，如果你想要的。